I bet it'll be in the late February sweeps batch of episodes. She seems a major guest star to be pimped for that period, especially in this show that features so many genre actors among the regular cast.

I'm very glad that Summer Glau is landing roles in non science fiction tv shows.
It's true that she has build her reputation in iconic roles in sci-fi series such as Firefly or Terminator: The Sarah Connor chronicles, or her recent recurring role on Alphas. However, she's a multi-faceted actress who has proven in the past that she can play a multitude of ages and she's a talented actress who deserves recognition outside of the sci-fi niche.

James Marsters was on the the pilot episode of Hawaii Five-O and was killed... or so we thought. As with all vampires, he comes back to life and appears two more times later in the series. lol
Also, Boo to Alphas being cancelled, that show was great from the start, and Summer's character was developing so awesomely.

Will it be too much to ask for her to not be insane or quickly go insane on this show? Granted, I don't know "Alphas", but "The Cape", she went nuts, and she was probably the most unhinged Greta on "Chuck".